Wireless devices often have a limited energy supply, such as a battery with a finite capacity. It is desirable that the wireless device uses the energy supply as efficiently as possible in order to prolong the useful operating period of the wireless device, before the energy supply requires recharging or replacing.
One way of prolonging the operating period of a wireless device is to power down some parts of the device during periods when the device is not required to perform any useful activity. For example, some wireless protocols periodically transmit a polling signal to maintain contact between devices in a network. In between the transmission of the polling signal, the transmitter and/or receiver can be powered down. The device has a reduced power consumption during the periods when it is powered down. Therefore, the wireless device has a reduced average power consumption and can be used for a longer period between recharges.
The embodiments described below are not limited to implementations which solve any or all of the disadvantages of known arrangements for power management of wireless devices.